Biological Imperatives
by Okami-chan
Summary: TFs as Dragons G1 AU. Chapter 1: Fuelling- In which Ratchet brings Prowl in out of the rain. Ties into the fic, Silver Purity, Cursed Crimson.


Chapter One  
Fueling

**Character/Pairings **Prowl, Ratchet (Prowl/Ratchet is if you put your mouth to one side and tilt your head to the other), Hound, Mirage  
**Summary** Ratchet uses a break in his work to bring Prowl out of the rain.  
**Author's Note **This takes place a few (and please take that with a grain of salt) chapters away from where I last left the Autobots. By this time they have left the Ark and Ironhide and Prowl have both ventured off on their own little adventure. More on that later, though. ;P

Many many thanks go to autumnsparrow for the beta, and to Tia for talking me through some of the difficult bits.

* translated from elven

* * *

A rich tapestry of smells sang across his olfactory sensors; musty, wet carbon compounds that covered this planet; air, heavy, almost saturated with water; the sharp sweetness of crushed chlorophyll; but above that, far more intriguing to his grinding fuel tanks, was the tangy scent of organic fluids, and exposed flesh. Ratchet paused at the entryway to the Ark, standing on the strange and fleshy surface that suddenly gave way to even stranger ground. He hadn't had much opportunity to come outside of the Ark to take in their new environment in the short time they had been online (several recharge periods, certainly, a_ week_* possibly.) He didn't count rushing out to the nearby stream to neutralize the acid eating Jazz's back. Optics accustomed to blues and grays blinked at the amount of green that covered everything on this new world. Brown poles reached up to support a green roof, and yet each segment of the roof was smaller than the pad on his fingertip. Needle like growth also matted the ground, but rather than stab, it created a cushion to the firmer ground made up of even tinier particles. Not just green covered the floor, but other colors, small spots of bright reds and vibrant blues, yellows and purples, and none of the plants looked the same from one variation to the next. Billions of tiny organisms that covered an unknown expanse of land, Astromiles? Megamiles? Certainly, not even Primus knew.

A whole world, untouched by technology, and the Cons had been plundering it for an uncertain amount of time. (How long was a _year_* when compared with a vorn? )

Ratchet shook his contemplation off. Empty fuel tanks seemed to make it easier for his processor to drift off in these organic shells, to lose himself to the sights and smells that surrounded him and drew involuntary responses from his odd body. He had more important things to do than concern himself with things he had no control over.

Prowl lay on a ledge off to the left and a little way from the entrance. His long frame coiled about like a length of cable, occupying all the available space, and yet still managing to drape his fuzzy aft tip over the edge (wasn't the word for that _tail_*). He faced away from Ratchet, looking off to the left, out towards the woods. The enticing smell of flesh and blood seemed to originate from him. Ratchet knew the tactician was damaged; it disgusted him that the smell of an old friend would start slimy lubricant coating the interior of his mouth.

"Karalee says it's going to rain. Are you coming inside?" Ratchet shifted from one hand to the other, his plates shuddering with every small droplet of water that fell from the clouded sky. The little elf had said there was nothing to worry about, but a lifetime with the corrosive precipitation of Cybertron made the medic cautious, almost fearful of any moisture that fell from the sky.

Prowl turned his head, his sinuous neck allowing him to pivot his head a full circle. Small streaks of red still decorated his normally pristine white plating, organic fluid (_blood* _Karalee had called it when the word _energon_ had baffled her) leaking from his long neck. Red now for those who had consumed the native fuel, instead of the pink from when they had first come online. Jazz and Optimus were the only ones left among those currently online to still have pink blood in their fuel lines. Red, the color of Primus, a color the organics on this world all contained. A color that Ratchet dreaded he would become all too familiar with, soon.

"Hound concurs with that conclusion." The tactician drew his feet closer to his body, curling his claws (more talons than claws, Ratchet thought) as though to hide the pink that stained them. A chill wind rippled across the fuzz on the back of his neck. "He's excited by the idea of clean water falling, and not having to run for cover."

"Hound?" Ratchet stepped farther out, arching his neck to the side to look for the green mech-beast. "What the slag is Hound doing out here?"

Sure enough, he could see the green silhouette perched on another ledge higher up, but not too far away. Hound certainly looked happy, large nasal openings (_nostrils*,_ didn't Karalee call them?) flaring wide as he almost audibly drew great droughts of air into his prominent olfactory sensor. Bright blue eyes took in his environment with all the attentiveness of an autolion with a bowl of motor oil.

Mirage curled at the tracker's feet, dead blue optics staring at Ratchet in trepidation. Even at this distance, Ratchet could sense the _wrongness _of the mech-beast, like Ironhide's clogged ventilators, and Jazz's malfunctioning optics, as well as Prowl's torn neck. The medic believed he could repair Ironhide, and Jazz. He would certainly beable to fix the damage done to Prowl's neck. Mirage, however, he could not repair; the noble mech had lost his spark.

Blood trailed up the cliffside, tufts of organic matter clinging to the spur rock along the mountain, leading to the two mech beasts. Mirage held something in his hands, ripping strips off and swallowing them, or alternatively handing the strip to Hound for consumption. The source of the enticing smells.

Watching them made Ratchet's tanks grind even louder, prompting a grumble from his vocalizer. He wanted nothing more than to go over there and take the chunk of flesh—whatever it was—from Mirage and shove it down his own tracheal tube. It would be easy; Mirage was small—much smaller than he—and _lesser_, it would never even occur to the sparkless drone to defend his property. A growl built up, rumbling from the medic's chest, as he continued to stare at Mirage. He approached the ledge Prowl lay on, judging the effort it would take to leap over the tactician, and scramble up the mountainside to reach Mirage.

Hound noticed Ratchet's scrutiny, and the green mech-beast tilted his head to one side in comical confusion. His nostrils flared again, audibly drawing in air. Confusion turned to alarm, and Hound sprang to his hands and feet, tail twitching agitatedly behind him.

The corners of Prowl's mouth turned down as he glanced between Mirage and Ratchet. His long neck stretched out, and he grabbed the edge Ratchet's chevron, drawing the medic's attention with a sharp shake. "Back off," the words barked out of his vocalizer, and his nasal ridge wrinkled, baring sharp dental plates.

It snapped Ratchet out of his strange mindset. The medic swallowed air, surprised by the sudden shift in whatever programming ran these alien bodies. Now, he wanted nothing more than to grovel and roll in the soft green foliage before Prowl. He wanted to abase himself and rub the tip of his nasal ridge against Prowl's jaw hinge in supplication as Mirage did to Optimus whenever the dumb mech-beast saw Prime. Such actions seemed undignified, and it took every ounce of his will to refuse to those needs; for his programming recognized Prowl as a _better_ the same as it viewed Mirage (and even Hound) as a _lesser_.

Glancing back up, he saw Mirage shrink against Hound's shining green plates. Hound rubbed the tip of his nasal ridge against the white ridges along Mirage's back, his optics and nostrils wide in what Ratchet could only presume was alarm.

Neither needed to worry, Ratchet wasn't about to make any moves toward him. Not only because of Prowl's command, but the sparkless mech-beast still made Ratchet's circuits crawl and he had no real desire to lay his hands on the white plating. Ratchet tore his gaze away from the smaller mech-beast, trying to ignore the lingering scent of flesh and organic fluids.

"Hound is our sentry. We'r-are vulnerable if we don't know an enemy is coming." The tactician pulled his head away, tilting his long face up at the medic. The angle revealed the bite on his neck; torn plating and fluids slowly leaking onto his pristine white paint. "Aren't you-" he interrupted himself with a hiss, and started over, each word enunciated carefully. "Are you not supposed to be resting?"

Ratchet claimed another step toward the black and white mech-beast, unable to tear his gazes away from the slowly leaking neck wound. "You should talk," he snorted. The occasional raindrop had graduated to a steady patter by now; chilled, wet needles that ran down his sides and chevron, dripping into his optics. His secondary shutters blinked at a steady rate, clearing the water out of his optics.

Prowl didn't even flinch, and this prompted Ratchet to take another step; his thicker textured casing a little better protected from the cold than Prowl's segmented plates (_scales*_, he reminded himself). "I'm- _am_ not the one reviving our fallen comrades with his own energy." The tactician gave him a pointed look. "It is depleting you, and that is making you irritable."

Ratchet's fuel tanks ground noisily just at that moment and Ratchet huffed, "It doesn't help when my workload is being added to by officers brawling."

Prowl jumped as though struck and Ratchet immediately regretted his choice of words. His long white tail lifted up only to thump angrily against the barren rock face. Ratchet almost shrank back at the glare Prowl directed his way. The red chevron accentuated the dip of his brow, unchanged from the glower that would have the twins standing at attention in less than an astrosecond.

Primus, did his lack of fuel also contribute to a lack of thought before speaking. "I'm sorry, that was uncalled for."

"No." Prowl tail twitched again, the fuzzy tip landing on the rock with a soft slap. "You're right. It was unnecessary. I'm, _am_ sorry for doing that when you're already overworked." His head lifted, changing his expression from angry to contrite in one simple gesture, but the pause before he spoke again was nearly tangible. "How is Jazz?"

A smirk pulled at the corner of Ratchet's mouth. "Oh, he'll function. He's recharging with Prime, Jack and Ironhide right now. The water neutralized your acid, I just need to make sure the self-repairs are working properly when he comes online again." His fuel tank complained again, accompanied by an uncomfortable grunt from the medic's air propelled vocalizer.

Prowl arched his neck, a gesture Ratchet could not interpret. "You need to refuel. Here." He reached down, his head disappearing under the edge of his ledge. He came back up, holding the hind end of some creature delicately between his dental plates.

Air burst from his nostrils, clearing the passageways to inhale the rich, metallic scent of fresh flesh. His mouth gaped and he panted hungrily, fixated on the rump waved at him. Still, that same programming that had nearly sent Ratchet after Mirage, kept him from simply snatching the thing from Prowl's jaws.

Translucent shutters slid over Prowl's optics, a questioning blink. "'Atchet?" he asked, speech slurred more than normal by the leg in his jaws. He moved the offering forward, tossing his head to maneuver the piece of flesh around his mouth.

Ratchet snorted again, pulling away from the offered rump. Primus, his fuel tanks practically churned from depletion, but he couldn't even bring himself to take the meat from Prowl's (his _better's)_ mouth.

Prowl watched him for only a few astroseconds more, and then he simply opened his mouth, letting the rump land at Ratchet's feet.

Ratchet watched Prowl coil his neck back across the ledge before he lunged for the meat. He ripped it apart, spilling the creature's cold internals only to slurp them into his waiting mouth. He swallowed chunks at a time, mouth sensor shoving the meat to his tracheal tube, which took over. He tore the rump down to its frame, dental plates scraping over the white framework, and glossa sliding over the meager remains for the last taste of fluid and flesh. He scooped the remains into his mouth and tossed them aside; discarded tid-bits of a once-living organism.

Something hovered above his head, teasing and taunting. A cloven foot brushed his nasal ridge, and Ratchet snapped his jaws on the fresh morsel. Ratchet . With a snarl, he pulled until he saw that Prowl still held onto the head and neck of the creature.

He froze, his fuel tanks demanding more, his programming screaming, _'Don't challenge __him__! Go after the _other_ one! Even the green one!' _

Prowl narrowed his optics, and then he grinned around the neck in his jaws, and let the tawny forequarters drop to the ground. He didn't wipe his mouth sensor over the fluids, but shook his head to rid his face of the red marks. What that didn't clean, the falling rain washed off.

Ratchet tore through that one, and several others that Prowl tossed front of him. His fuel tanks didn't seem the least sated until he had consumed six of Prowl's offerings. Even then, he didn't feel satiated, but the grinding in his fuel tanks had abated, and he glanced up at Prowl.

The tactician watched him, water running off his nasal ridge and dripping off the end. Prowl noisily snorted his nasal passages to clear the water that tried to pool in their grooves. The black fluff on the back of his neck no longer waved freely, now it clumped together, sagging under the weight of the water falling from the sky. A rumble rolled through the white frame, a short gasp of air released, like the pop of a bubble in a chemical vat.

Ratchet narrowed his optics, and turned his full attention on Prowl. He could see and sense the damage done to Prowl's exterior plating, but below that he also smelled a system running only on fumes (at least, that was the closest comparison he could come up with for their organic shells). "Why don't you refuel? Before I consume everything you've managed to catch."

"Mirage caught it, and insisted on leaving it with me. He's not stopped retrieving fuel supplies while I've-_have_ been here. I allowed him, so that we might have ample fuel," Prowl stretched his neck out to glance at his almost hidden stockpile of fuel. "Running out isn't a concern currently, unless Ironhide or Prime should join us as well. They're- _are_ both recharging, correct?"

Ratchet stood, taking the few steps that would bring him around to the front of Prowl's ledge. He grunted in surprise at the amount of corpses strewn about the bottom of the ledge. Ratchet quickly swallowed the piece he still had in his mouth and snagged two more whole bodies. He broke the first one in half, letting the rear portion fall to the soft green ground.

The other half of the creature he held up and offered to Prowl. "Refuel," he said, his words slurring messily around the shoulder in his mouth.

Prowl huffed, long neck curving to pull his head away from Ratchet's offering. "You need it more than I do."

Ratchet hefted his shoulders and chest onto Prowl's ledge. The heavy, black fuzz clung to his hide, sliding off only reluctantly at the end of their reach. Ratchet dropped the rump just beside Prowl's hand.

The white nostrils closed, and Prowl jerked away with a noisy protest. Prowl houghed again, shoving himself away from the medic, but Ratchet threw an arm over the white wing panels, and held the smaller mech-beast still with his greater weight.

Prowl's neck slung away from Ratchet's jaws, and his nasal ridge wrinkled, exposing his dental plates in a snarl. "Finish refueling, that's an order.".

Ratchet gritted his own dental plates, lip components pulled back to mirror the tactician's glower. "What the slag do you think I've been doing, but you haven't even touched any of these… things. You're running on fumes, and you're damaged. We don't know the endurance of these shells, so _I'm_ telling _you_ to refuel, medical orders."

Pointy dental plates snapped together just before Ratchet's optics, and Prowl snarled. His lower body twisted, and one of his legs grabbed the curve of Ratchet's shoulders. Talons dug into white hide, and Ratchet froze, remembering what had happened when Jazz had yanked himself free of the tactician's grasp, how badly they had torn the blind mech-beast's slicker skin. His hands bit into the rock, digging a neat groove as he tried to shove the medic off, and Prowl's head hovered above Ratchet's swaying back and forth with a continuous hiss. "I'm-_am_ not going to recycle parts like this. There has to be another way to refuel these forms."

Ratchet hunched down at an unspoken signal, his organic programming recognizing the threat of Prowl's movements even when his processor made no sense of the actions. Conflict held Ratchet fast for a moment, Prowl was his _better,_ but not in this. In this Ratchet was _better_, and Prowl _lesser_. His tail twitched, and a growl rumbled deep with in his chest. "That may be the case, but we don't have time to discover what else we could use. You think that I enjoy knowing that my fuel is coming from consuming helpless organics?" Ratchet didn't miss the translucent shutter sliding over Prowl's optics, but it only served to infuriate the medic even more. "It's not like we have a choice! It's simple survival, Prowl, even your primitive logic centers should tell you that."

"Prowl, is everything okay?" Hound's voice floated down to the two mech-beasts on the lower ledge. Even Mirage's whine sounded more distance than simple height could explain.

Prowl's head snapped toward the scout, his optics glowing in anger. He glared up at the other two, and then just as suddenly he sagged as though all of his hydraulics had gone out. "Everything's fine," he replied without inflection. He released Ratchet like the medic was burning hot, and huddled under the larger mech's frame. His exertions had opened the delicate seal his body had created over his damaged neck, and thin lines of red fluid ran down the white scales. "It is simple logic. You top off, first though. I'd like to hold off as long as I can so the more useful among us are guaranteed their fuel."

Hound forgotten, Ratchet turned a searching eye on the other mech-beast. Prowl, while often more than capable of working himself past the point of exhaustion, rarely treated his needs as less important than others. "You make it sound as though you aren't doing anything." He was still perfecting how to read the new body language and facial features, but the drooping membranous panels on Prowl's shoulders still seemed to convey the tactician's dejected state of mind.

Prowl turned away from Ratchet's scrutiny, a casual movement to look back at the sky. Ratchet knew better though, and a growl rumbled from his massive chest, and his claws bit into the ground as he shifted his weight irritably.

Prowl's brow drew down, drawing the skin around his bony chevron into tight lines. "What good am I?" His lips lifted, releasing a hiss from between his smooth teeth—teeth stained as pink as his talons. His gaze dropped down to his fingers and the curved talons that tipped them, he scraped them over the coat of pink, as though to remove the reminder of what he'd done. "I can't—cannot touch anyone with these hands. I can't-not see the patterns that should be so obvious." The wind rustled his wild mane, the black strands whipping across the scales of his neck and tangling across his chevron. He stared at his hands, but he didn't seem to see them. His plating shivered with remembered movement, spattering drops of red across the ground. "What good am I without my battle computer? Might as well hand Ironhide my position, he'd make a better tactician than I am at this time. Look how easily I lost my temper at Jazz, and how badly I damaged him before Optimus and Ironhide stepped in. How can I be of any use if I cannot even keep my calm in a stressful situation? "

As Prowl spoke, Ratchet's head drew farther and farther back. Suddenly he lashed out, thunking the bottom of his jaw against the other mech-beast's neck.

Prowl yelped, turning wide blue eyes on the medic.

Ratchet walloped him across his long nose and then shoved his own chevron against the red one on the tactician's forehead (_horns*_). "This has not made you useless. We're in a strange situation that has changed what we're capable of, all of us." Their bone horns creaked together, but Ratchet could not see past his low brow ridge, and he wanted to look Prowl in the optic. Shaking his horns free, he nipped at Prowl's nasal ridge, elongated dental plates catching but not penetrating smaller scales that lined the top of his nasal ridge. He looked Prowl straight in one of his blue optics. "You are not useless, you slagger."

Prowl jerked away from Ratchet, standing on shaky legs. The rain fell in a torrent now, rhythmically pattering across their bodies. It drenched Prowl's mane, leaving it clinging to his white scales, and tangled on his chevron. "You can say that, when you haven't been there to see how little I've done. Losing my temper was not the first of it. If I were at full capacity I don'-not think that Ironhide and I would have been captured so easily; I would have seen through that trap; I would have realized your problem was as simple as an insufficient fuel supply-"

"Would you stop that!" Ratchet barked, his words ringing across the solid rock and sending a flight of small organics into the sky. He twisted his head around to glare Hound back, not wanting the scout to interfere. "You're dealing with too much 'would have's and 'could have's. Stop it. Look at what you have done. No one thought to set a watch, but you did. You have provided fuel for those online, albeit through a third party. You might have gotten captured, but you still returned with Ironhide, and even managed to bring Mirage back with you, as well as someone who could help us with our situation. And don't," Ratchet snarled when he saw Prowl's jaw open to object, "tell me you had nothing to do with that. You could have easily and illogically decided that she had been involved with those _humen*_ and killed her. You planned out the order in which to bring everyone online. And as for Jazz, well," Ratchet's tail twitched with his irritation at the saboteur, "that slagger has very bad timing He should have kept it on mute. You've been patient with him for longer than I ever could have been in your position."

Prowl frowned, venting a long sigh in frustration. "I can't—can_not _refute you at this moment. My processors seem too clogged up to manage that."

Ratchet hefted the second corpse he had snagged and plopped it along with the half already in front of Prowl. "Refueling would solve that. Then, if you're done feeling sorry for yourself, the twins are up next, and I want you there. But first, I'm going to recharge before I bring their sorry shells online. It's slagging cold in the Ark, and Ironhide sounds like he's gunning his engine every time he intakes. Hound is perfectly capable of sentry without you presiding."

Prowl's face wrinkled in a peculiar way, but he picked the whole corpse up and tore a piece away from the brown flank. "Then I suppose we should make sure you have you are comfortable enough recharge. I _will_ need the energy to deal with Sideswipe and Sunstreaker's antics." He did not have to say that he would not like it, but then again, Ratchet didn't' think he needed to.


End file.
